This book is an attempt to explain to the world at large what goes on in the world of computers. So it's not just for programmers. For example, Chapter 6 is about how to get rich. I believe this is a topic of general interest.

You may have noticed that a lot of the people getting rich in the last thirty years have been programmers. Bill Gates, Steve Jobs, Larry Ellison. Why? Why programmers, rather than civil engineers or photographers or actuaries? "How to Make Wealth" explains why.

The money in software is one instance of a more general trend, and that trend is the theme of this book. This is the Computer Age. It was supposed to be the Space Age, or the Atomic Age. But those were just names invented by PR people. Computers have had far more effect on the form of our lives than space travel or nuclear technology.

Everything around us is turning into computers. Your typewriter is gone, replaced by a computer. Your phone has turned into one. So has your camera. Soon your TV will. Your car has more processing power in it than a room- sized mainframe had in 1970. Letters, encyclopedias, newspapers, and even your local store are being replaced by the Internet. So if you want to understand where we are, and where we're going, it will help if you understand what's going on inside the heads of hackers.

Hackers? Aren't those the people who break into computers? Among outsiders, that's what the word means. But within the computer world, expert programmers refer to themselves as hackers. And since the purpose of this book is to explain how things really are in our world, I decided it was worth the risk to use the words we use.

The earlier chapters answer questions we have probably all thought about. What makes a startup succeed? Will technology create a gap between those who understand it and those who don't? What do programmers do? Why do kids who can't master high school end up as some of the most powerful people in the world? Will Microsoft take over the Internet? What to do about spam?

Several later chapters are about something most people outside the computer world haven't thought about: programming languages. Why should you care about programming languages? Because if you want to understand hacking, this is the thread to follow—just as, if you wanted to understand the technology of 1880, steam engines were the thread to follow.

Computer programs are all just text. And the language you choose determines what you can say. Programming languages are what programmers think in.

Naturally, this has a big effect on the kind of thoughts they have. And you can see it in the software they write. Orbitz, the travel web site, managed to break into a market dominated by two very formidable competitors: Sabre, who owned electronic reservations for decades, and Microsoft. How on earth did Orbitz pull this off? Largely by using a better programming language.

Programmers tend to be divided into tribes by the languages they use. More even than by the kinds of programs they write. And so it's considered bad manners to say that one language is better than another. But no language designer can afford to believe this polite fiction. What I have to say about programming languages may upset a lot of people, but I think there is no better way to understand hacking.

Some might wonder about "What You Can't Say" (Chapter 3). What does that have to do with computers? The fact is, hackers are obsessed with free speech. Slashdot, the New York Times of hacking, has a whole section about it. I think most Slashdot readers take this for granted. But Plane & Pilot doesn't have a section about free speech.

Why do hackers care so much about free speech? Partly, I think, because innovation is so important in software, and innovation and heresy are practically the same thing. Good hackers develop a habit of questioning everything. You have to when you work on machines made of words that are as complex as a mechanical watch and a thousand times the size.

But I think that misfits and iconoclasts are also more likely to become hackers. The computer world is like an intellectual Wild West, where you can think anything you want, if you're willing to risk the consequences.

And this book, if I've done what I intended, is an intellectual Western. I wouldn't want you to read it in a spirit of duty, thinking, "Well, these nerds do seem to be taking over the world. I suppose I'd better understand what they're doing, so I'm not blindsided by whatever they cook up next." If you like ideas, this book ought to be fun . Though hackers generally look dull on the outside, the insides of their heads are surprisingly interesting places.